Polarized magnetic-operating device



April 21, 1959 J. M. JOHNSON POLARIZED MAGNETIC-OPERATING DEVICE FiledAug. 20; 1956 FIG. I

:tures 25 and 26 respectively,

United States Patent Ofiiice 2',ss3,ss9 POLARIZED MAGNETIC-OPERATINGDEVICE Leonard M. Johnson, Downers Grove, 111., assignor toInternational Telephone and Telegraph Corporation, New York, N.Y., acorporation of Maryland Application August 20, 1956, Serial No. 604,9548 Claims. Cl. 317-171) This invention relates to a polarizedmagnetic-operating device. The principal object of the invention is toprovide a device of this character which combines sensitivity andrelative load-handling ability with rugged dependability, to thusrequire a minimum of operating current and preferably requiring noholding current.

In known forms of construction, sensitivity has been enhanced byproviding the armature of the polarized electromagnetic structure in theform of a load-carrying permanent magnet, and the ability of thearmature to move its load from one position to the other has beenenhanced by a lost-motion technique wherein the load is encountered onlywhen the armature is most powerful-is approaching its final position ineither direction of movement. One objection to the above form ofconstruction is a rather complex pivoting or journaling arrangementrequired to provide for both the turning and the lost-motion action ofthe magnetized load armature.

According to the invention, the construction is simplified by replacingthe lost-motion action of the load armature by the idle motion of one ormore secondary armatures to adjust the operating gaps of the loadarmature according to the required direction of movement, therebypermitting the load to be directly coupled without lost motion.

The above-mentioned and other features and objects of this invention"and the manner of attaining them will become more apparent and theinvention itself will be best understood, by reference to the followingdescription of an embodiment of the invention taken in conjunction withthe accompanying drawings comprising Figs. 1 to 4, wherein:

Figs. 1 and 2 are respectively top and front views of the device havingcertain parts removed;

Fig. 3 is a sectional view taken generally along line 3-3 of Fig. 2; and

Fig. 4 is an enlarged fragmentary view showing the armatures in theiralternative position.

Referring to the drawings, comprising Figs. 1 to 4, the

polarized magnetic-operating device includes a pair of e'lectromagnets14 and 15, having pivotally secured armaa permanent-magnet airmatureassembly 29, a pair of switch assemblies 39 and 40 actuable by armatureassembly 29 responsive to energization of electromagnets 14 and 15 and agenerally inverted U-shaped bar 5 together with a connecting bar forminga generally open-end box-like magnetic structure having these partssecured thereto.

The open-end box-like structure (members 5 and 10) provides the magneticreturn path for the structure and having the permanent-magnet armatureassembly 29 mounted therein greatly reduces the efiect of adjacentmagnetic fields on the operation of the device.

Referring particularly to Fig. 2, inverted U-shaped bar .5 includes ahorizontal top portion supporting the switch assemblies 39 and 40, adepending vertical left portion 6 supporting the electromagnet 14, and adepending vertical right portion 7 supporting electromagnet 15. Bar 5 is2,883,589 Patented Apr. 21, 1959 between horizontal mounting members 1by mounting brackets 3 which are secured to members 1 by screws 2. Eachmounting bracket 3 is provided with an aperture for receiving thethreaded end of a core 20 and is rigidly secured thereto by a nut 21.Other similar devices may be supported adajcent to the one illustrated,to form the relay apparatus of a telephone switchboard.

Each of the electromagnets 14 and 15 includes a coil 18 and lacylindrical magnetic core 20 extending therethrough. One end of eachcore 20 is threaded which is received within an opening within thedepending vertical portions 6 or 7 of bar 5 and mounting brackets 3 andrigidly secured thereto by means of a nut 21.

Each coil 18 loosely encircles its core 20, and is provided withgenerally square spool heads 16 and 17.

Each spool head 17 is provided with terminals 19 for extending a localconnection from the coil to terminals 61.

Each inwardly extending end portion of core 20 is provided with anarmature 25 or 26 pivotally secured within a slot 22 by means of a rivet27 (Fig. 4). Each of the cores 20 is provided with a spring 24, rigidlysecured thereto as by staking abutting spool head 16. The free ends ofadjusting springs 24 are offset and are readily adjustable, as bybending, to provide stop positions for their associated armatures 25 or26.

As shown in Fig. 2, each depending portion 6 and 7 of bar 5 terminatesin a flange portion 8 to which is secured a magnetic supporting bar 10by screws 11.

As shown in Fig. 3, the permanent-magnet armature assembly 29 ispivotally secured to support bracket 32 between pivot pin 35 and pivotscrew 36 for a back and forth movement between stop members 55 (Fig. 4).Pivot pin 35 is secured to the generally Ushaped bracket 32 as byriveting, and pivot screw 36 is threadedly received within an opening inthe upright portion of bracket 32 rendering it Iadjustable. A lock nut(not shown) is generally provided to retain the pivot screw in a desiredposition of adjustment.

Support bracket 32 is secured to bar 10 (Figs. 2 and 3) by screws 34which are received within openings in bracket 32 and threadedly engageclamping plate 33.

As shown in Figs. 2 to 4, the permanent magnet 30 is secured within thebox-like bracket 31 by means of shear-formed tabs 70, two such tabsbeing shown in Fig. 4. The north pole of magnet 30, for example, isassociated with the upper portion of armatures 25 and 26, while itssouth pole is associated with the lower portion of the armatures. Thearmature bracket 31 includes a pair of upwardly extending arms 71terminating in an enlarged portion 72 having an insulating bar 37extending between the arms for actuating the switch assemblies 39 and40. The back and forth movement of armature assembly 29 is limited bythe engagement of portion 72 with stop members 55, one position beingshown in Fig. 2 while its alternate position is shown in Fig. 4.

A non-magnetic plate portions 55 is secured of bar 5 together withscrews 56 and nuts 58. spaced relationship with spacers 57.

Insulating plate 60 is provided with terminals 61; the lower portionthereof is used for terminating local conductors extended from terminals19 of electromagnets 14 and 15, and the spring terminals of stackups 39and 40, two such conductors are shown in Fig. 2. The upper portion ofterminals 61 are used for connecting external conductors (not shown).

For convenience, the switch assemblies (39 and 40) supportedhorizontally are illustrated as being all alike. Ordinarily, theassemblies may vary according to the different circuit functions.

Each switch assembly 39 and 40 comprises two adjacent stackups (Fig. 1).Considering the switch assemblies as shown in Fig. 2, each such stackupof switch assembly 39 includes two commonly denoted types of contactsets, a make set (fixed blade 43 and traveling springs 42) and a breakset (fixed blade 44 and traveling springs 45). Each stackup of switchassembly 40, similarly includes a break set (fixed blade 47 andtraveling springs 46), and a make set (fixed blade 48 and travelingsprings 49).

Each fixed blade 43, 44, 47, and 48 carries a molded insulated guidemember 85 serving as guide means for the relatively flexible travelingsprings 42, 45, 46 and 49 which comprise a pair of adjacent wires. Thefixed blades and the traveling springs are maintained in assembledrelationship by having their outer portion secured in a block of moldedinsulating material which is secured to nonmagnetic plate 54 by aU-shaped clip member 41. The fixed blades and traveling springs have aportion extending beyond the molded portion serving as a terminal memberfor local connections therewith.

As shown in Fig. 4, the inwardly extending end portions of travelingsprings 42, 45, 46, and 49 are cammed either upwardly or downwardly byinsulating bar 37 responsive to the movement of the armature assembly29.

The armatures 25 and 26 are adapted for a back and forth turningmovement with respect to the similar movement of armature assembly 29between the position shown in Fig. 2 and the position shown in Fig. 4responsive to control of electromagnets 14 and 15.

With armature assembly 29 together with armatures 25 and 26 in theposition shown in Fig. 2, energization of electromagnets 14 and 15 inthe proper direction renders armature 25 magnetically south whilerendering armature 26 magnetically north thereby causing the freelymoving armatures 25 and 26 to be turned from the position shown in Fig.2 to the postion shown in Fig. 4. Such movement shortens the operatinggap (between unlike poles) corresponding to the new position andlengthens the operating gap corresponding to the initial position. Theflux passing through the shortened operating gap then quickly turns(snap-like action) armature assembly 29 from the position shown in Fig.2 to the new position shown in Fig. 4. The shortening of the effectiveoperating gap for 29 by the preliminary movement of armatures 25 and 26reduces the amount of flux necessary to turn armature assembly 29.

The movement of armature assembly 29 to its new position shown in Fig. 4permits pretcnsioned traveling springs 42 to close a circuit includingfixed blade 43 while camming springs 45 downwardly out of engagementwith its fixed blade 44. Similarly, traveling springs 46 are cammedupwardly out of engagement with its fixed blade 47 while permitting itstraveling springs 49 to close a circuit including fixed contact blade48. The armature assembly 29 is held against left stop 55 by the localflux of magnet 30 passing through the operating gaps in series and isfurther retained by springs 42 and 49.

The operate circuit for electromagnets 14 and 15 is generally opened atits own contacts (for example, at 44 and 45 of switch assembly 39) toavoid further current drain.

Energization of the electromagnets 14 and 15 in the opposite directionresults in the turning of freely moving armatures 25 and 26 followed bythe turning movement of armature 29 thereby returning them to a positionas shown in Fig. 2.

While I have described above the principles of my invention inconnection with specific apparatus, it is to be clearly understood thatthis description is made only by way of example and not as a limitationto the scope of my invention. Y

and pairs of operating I claim:

1. A polarized magnetic-operating device comprising a pair of armaturesand means for turnably supporting each for a back and forth turningmovement with respect to the other armature and between a first positionand a second position, the armatures being separated by first and secondoperating gaps corresponding respectively to the said positions ofeither armature, separate and relatively fixed stop means for eacharmature defining the said positions thereof, movement of eitherarmature from either position'thereof to the other lengthening oneoperating gap and shortening the other, means including a source of fluxexternal to the armatures for passing operating flux through them inseries in a path which eifectively includes the two operating gaps inparallel, and means for magnetically polarizing the operating gaps withrespect to the flux direction of the external source, comprising meansfor passing flux locally through the operating gaps in series, wherebythe flux from the external source traverses the operating gapsselectively according to the direction of such flux, to thereby urge thearmatures in the corresponding direction.

2. In a device according to claim 1, the said external fiux sourceincluding an electromagnet comprising a magnetic core having first andsecond separated poleends and an encircling winding for magnetizing thecore longitudinally to impart opposite magnetic polarities to the poleends, the said first pole end being associated with one armature whilethe said second pole end is associated with the other armature forserially passing operating flux through them.

3. In a device according to claim 1, the said meansfor magneticallypolarizing the said operating gaps comprising one of the said armaturesin the form of a permanent magnet having pole faces at the respectiveoperlating. gaps.

4. In a device according to claim 1, means for coupling an operatingload to one armature while leaving the other armature relatively free toturn, whereby tihe freely moving armature turns first to thereby shortenthe operiating gap through which the loaded armature is turned.

5. In a device according to claim 1, the said external flux sourceincluding a pair of serially related electromagnets associatedrespectively with the arm'atutres, eachelectromagnet comprising amagnetic core having first and second separated pole ends and anencircling winding for magnetizing the core longitudinally to impartopposite magnetic polarities to the pole ends, one pole end of eachelectromagnet being physically adjacent to the associated armature,while the remai g pole ends are magnetically associated with each otherin a path independent of the armatures.

6. In a device according to claim 1, an additional armature so locatedrelative to the first two armatures as to comprise the third armature ina row of three upright and side-by-side armatures, support and stopmeans for the third armature providing a mutual turning and stoppingaction and mutual operating gaps between the second and third armaturesas set forth for the first two, the turning movement of the armlaturesbeing within the said row, the said external source for passingoperating flux being effective to pass flux through the row of armaturesgaps in series, and the said means for polarizing the operating gapscomp-rising means for maintaining a local longitudinal magnetization ofthe second armature.

7. In a device according to claim 6, means for coupling an operatingload to the said locally magnetized second armature while leaving thesaid first and third armatures relatively free to turn, whereby thefreely moving armatures turn first to thereby shorten the operating gapsthrough which the loaded second armature is turned.

8. In a device according to claim 7, the said external flux sourceincluding a pair of serially related electromagnets associatedrespectively with the said first and third armatures, each electromagnetcomprising a magnetic core having first and second separated pole endsand an encircling Winding for magnetizing the core longitudinally toimpart opposite magnetic polarities to the pole ends, one pole end ofeach electromagnet being physical- 1y adjacent to its said associatedarmature, while the remaining pole ends are magnetically associated Witheach other in a path independent of the armatures.

References Cited in the file of this patent

